NZPhotographer Issue 45, July 2021

HISTORY
If you’ve been playing around in Ps and you’ve made
some mistakes. Edit -> Undo (whatever you last did)
will always be available to you but there’s a faster
keyboard shortcut: Ctrl - Z (Windows) or Command - Z
(Mac). Press both keys together as many times as you
like to undo one step at a time. If you made several
mistakes or want to keep track of what you’ve done
so far, you can use the History panel. This is set by
default to be the top-most icon in the panel dock and
is indicated by a set of 3 cubes with a curved arrow.
Click the icon to see a list of your recent history.
The History panel populates with every action you take in Ps but only
remembers a set number of actions. It is a safety net if you make a
mistake within this set number of actions.
LAYERS
Imagine you have a few sheets of regular plain paper,
each with something different printed on them,
stacked into a pile. You have made the equivalent of
Ps layers. You know there are several sheets of paper
in the pile but you can only see the top sheet. If you
take off the top sheet, you’ll see the one underneath.
That’s how pixel-based layers work (e.g. anything with
a photo or image, or created using a pixel-based tool
such as the paint brush).
Open up an image in Ps and you’ll see it in the Layers
panel. Typically, it will be named the Background layer
and it will have a little padlock next to it. This means the
layer is locked. You can’t do anything much with a locked
layer (options will be greyed out) so unlock it by clicking
once on the padlock and the icon will disappear. The
layer will now be named Layer 0. You can rename layers
by double clicking on the type of the existing name. If you
double click elsewhere on the layer, you’ll get the Layer
Styles dialogue box which allows you to add funky effects
and blending to layers (make a note to have a play with
this later). To the left of the layer name is a small thumbnail
image and left of that is an eye icon. Clicking on this eye
icon will turn the layer on or off so you can see the layer
underneath. Clicking on a layer once will highlight that
layer and you can then use the icons at the bottom of
the Layers panel (highlighted in the following screenshot).
There are usually many ways to do the same thing within
Ps, so I will just talk about my preferred methods for creating
and altering layers using these icons. Again, Ps helpfully
includes information on what the icons are if you hover the
mouse pointer over them.
From right to left; the trash can deletes layers, the + inside a square
creates a new layer, the folder icon groups layers together inside a
folder, the half dark and light circle opens the adjustment layers menu,
and the light rectangle with a dark circle inside creates a layer mask.
The fx icon opens the Layer Styles dialogue box and the chain icon links
multiple layers together so any adjustments made to one layer apply to
all linked layers.
If you open two images into Ps, they will appear
in 2 separate files. Click and drag the layer of the
first image up towards the file tab for the second
image, hold it there until Ps swaps over to the
second tab, then drop the file onto the second
image. Alternatively, copy-paste an image into
an existing Ps document and it will appear as an
additional layer. Either way, you should now have
two images on separate layers in the same file.
Create a new layer using the New Layer icon and
you won’t see anything change on your image
because the layer is blank and transparent until
you put something on it. When you create a new
layer, the new layer is automatically selected
which means you are now working on this
highlighted layer. Add some paint using the paint
brush tool to this layer and it will appear over the
top of the layer below. Don’t like what you did?
Erase it using the eraser tool – only the paint on this
layer will be erased. If you were to paint directly
on your image layer rather than this new layer, it
would be destructively changing the pixels and
the eraser tool would erase your image as well as
the paint you put down on it. The key to working
non-destructively is to never alter the pixels on your
original image layer by instead using additional
layers to make changes and edits. Yes, you can
duplicate your background layer and make
destructive changes to that copy, but there are
several problems with doing it this way (although
many do) including doubling your file size.
NZPhotographer
July 2021
49